Query to find size of BLOB objects

what the size is of that BLOB object.

In order to find out the size of LOBs in your database, you'll want to use the DBMS_LOB supplied PL/SQL package, specifically the GETLENGTH procedure. The Oracle docs give the following example on determine the LOB size:

 CREATE OR REPLACE PROCEDURE Example_11a IS lobd BLOB; length INTEGER; BEGIN -- get the LOB locator SELECT b_lob INTO lobd FROM lob_table WHERE key_value = 42; length := dbms_lob.getlength(lobd); IF length IS NULL THEN dbms_output.put_line('LOB is null.'); ELSE dbms_output.put_line('The length is ' || length); END IF; END;

Basically, you get the LOB locator from your table. This locator points to the LOB. Using this locator, you call the DBMS_LOB.GETLENGTH procedure to determine the LOB size.

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